Gas strippers are generally used in a physical separation process where one or more components are removed from a liquid stream by a vapour stream, the streams flowing in counter current directions. For example in nuclear plants, such gas strippers may be generally utilized for purification of primary coolants that are circulated along the nuclear reactors for cooling. Generally, the primary coolants are circulated along the nuclear reactors to continuously cool the reactors. As the coolant is circulated during the cooling process, the coolant becomes contaminated by dissolved radioactive gases, among other things. Therefore, it is necessary to continuously purify and clean the coolant to remove the contaminants and to avoid discharge of hazardous elements to the environment. In general, a very high degasification factor (e.g., 106) is needed in order to remove radioactive gases, such as, for example, Xenon and Krypton. The known coolant cleaning processes usually involve two main treatment steps. First, to concentrate the coolant, and then secondly, to remove the radioactive gases by stripping. In the stripping process, a cleaning agent, such as boric acid, may be sprayed into the upper part of the stripping column and, as it flows down the column, it flows through sieve trays in order to increase the contact time between the liquid and gas streams. In the case of sieve trays, the contact area may not be well defined and changes with the flow regime and the steam velocity.
Various conventional gas strippers have been developed and utilized for this purpose. In designing the gas strippers, one of the most important and determining criteria is designing it in order to have sufficient contact between the liquid and vapour streams. There remains an industrial challenge to achieve a balance between the energy and costs needed in order to gain maximum contact between the liquid and vapour phases.
Accordingly, there exists a need for a gas stripper with improved design so that efficiency of the overall system may be improved.